234 PROCEEDINGS OF THE AMERICAN ACADEMY 



The thanks of the Academy were voted to Professor Gray 

 for his efficient services as Corresponding Secretary. 



Professor Peirce proposed that special meetings of the 

 Academy should be holden on the first Tuesdays in June and 

 July, at four o'clock, P. M. 



Voted, that such meetings be holden. 



Three hundred and thirty-third meeting. 



June 4, 1850. — Monthly Meeting. 



The President in the chair. 



Dr. A. A. Gould declined serving as a member of the Com- 

 mittee of Publication, and Professor Joseph Levering was 

 nominated by the chair, and unanimously chosen, to fill the 

 vacancy. 



Professor Agassiz presented some new views respecting the 

 coloration of animals. He stated that the coloration of the 

 lower animals living in water depends upon the condition, 

 and particularly upon the depth and transparency, of the 

 water in which they live ; that the coloration of the higher 

 types of animals is intimately related to their structure ; and 

 that the change of color which is produced by age in many 

 animals is connected with structural changes. He stated 

 that coloration is valuable as an indication of structure ; that 

 it is a law universally true of vertebrated animals, that they 

 have the color of the back darker than that of the sides ; and 

 that the same system of coloration prevails in all the species 

 of a genus, — partially developed in some, but recognizable 

 when a large number of species is examined. 



Professor Peirce expressed the opinion, that there are errors 

 in the lunar theory that still remain to be investigated ; that 

 occultations cannot be relied on as a means of accurately de- 

 termining longitude ; and that they are of little use for any 

 purpose, except when whole groups of stars, as the Pleiades 

 or Hyades, are taken. 



